|name|pos.|caps|goals|club|
|---|---|---|---|---|
|Olle Åhlund|MF|1|0|Degerfors IF|
|Sune "Mona-Lisa" Andersson|MF|5|0|AIK Solna|
|Henry "Garvis" Carlsson|FW|2|0|AIK Solna|
|Rune "Killing" Emanuelsson|MF|2|0|IFK Göteborg|
|Thure Grahn|DF|1|0|IS Halmia Halmstad|
|Gunnar "Il Professore" Gren|FW|5|5|IFK Göteborg|
|Sven "Jack" Jacobsson|MF|1|0|GAIS Göteborg|
|Egon "Hemliga" Jönsson|FW|1|0|Malmö FF|
|Börje Leander|MF|1|0|AIK Solna|
|Nils "Lidas"/"Greven" Liedholm|FW|6|5|IFK Norrköping|
|Torsten "Lindy" Lindberg|GK|5|0|IFK Norrköping|
|Lennart Lindskog|FW|1|0|Degerfors IF|
|Malte "Svarta Blixten" Mårtensson|FW|2|0|Hälsingborgs IF|
|Erik Nilsson|DF|4|0|Malmö FF|
|Harry Nilsson|DF|2|0|AIK Solna|
|Ove Nilsson|GK|1|0|Djurgårdens IF Stockholm|
|Stellan Nilsson|FW|4|0|Malmö FF|
|Bertil Nordahl|MF|4|0|Degerfors IF|
|Gunnar Nordahl|FW|6|8|IFK Norrköping|
|Knut Nordahl|DF|5|0|IFK Norrköping|
|Stig Nyström|FW|1|1|Djurgårdens IF Stockholm|
|Kjell Rosén|MF/FW|4|0|Malmö FF|
|Birger "Bian" Rosengren|MF|1|0|IFK Norrköping|
|Rolf Svensson|FW|1|0|Hälsingborgs IF|
|Börje Tapper|FW|1|1|Malmö FF|

Question: how many defensive (df) players are there on the national team?
Answer: 4